From a3dd1c817058eab96fd99f1f8b54ece2e2a0df04 Mon Sep 17 00:00:00 2001
From: Matt Arsenault <Matthew.Arsenault@amd.com>
Date: Tue, 10 Jun 2014 20:10:08 +0000
Subject: [PATCH] Fix error in tablegen when either operand of !if is an empty
 list.

!if([Something], []) would error with "No type for list".

llvm-svn: 210572
---
 lib/TableGen/TGParser.cpp          | 14 ++++++++------
 lib/TableGen/TGParser.h            |  2 +-
 test/TableGen/if-empty-list-arg.td |  7 +++++++
 3 files changed, 16 insertions(+), 7 deletions(-)
 create mode 100644 test/TableGen/if-empty-list-arg.td

diff --git a/lib/TableGen/TGParser.cpp b/lib/TableGen/TGParser.cpp
index f337c75ed5e..0550692ebce 100644
--- a/lib/TableGen/TGParser.cpp
+++ b/lib/TableGen/TGParser.cpp
@@ -787,7 +787,7 @@ Init *TGParser::ParseIDValue(Record *CurRec,
 ///
 /// Operation ::= XOperator ['<' Type '>'] '(' Args ')'
 ///
-Init *TGParser::ParseOperation(Record *CurRec) {
+Init *TGParser::ParseOperation(Record *CurRec, RecTy *ItemType) {
   switch (Lex.getCode()) {
   default:
     TokError("unknown operation");
@@ -1026,8 +1026,9 @@ Init *TGParser::ParseOperation(Record *CurRec) {
     }
     Lex.Lex();  // eat the ','
 
-    Init *MHS = ParseValue(CurRec);
-    if (!MHS) return nullptr;
+    Init *MHS = ParseValue(CurRec, ItemType);
+    if (!MHS)
+      return nullptr;
 
     if (Lex.getCode() != tgtok::comma) {
       TokError("expected ',' in ternary operator");
@@ -1035,8 +1036,9 @@ Init *TGParser::ParseOperation(Record *CurRec) {
     }
     Lex.Lex();  // eat the ','
 
-    Init *RHS = ParseValue(CurRec);
-    if (!RHS) return nullptr;
+    Init *RHS = ParseValue(CurRec, ItemType);
+    if (!RHS)
+      return nullptr;
 
     if (Lex.getCode() != tgtok::r_paren) {
       TokError("expected ')' in binary operator");
@@ -1446,7 +1448,7 @@ Init *TGParser::ParseSimpleValue(Record *CurRec, RecTy *ItemType,
   case tgtok::XIf:
   case tgtok::XForEach:
   case tgtok::XSubst: {  // Value ::= !ternop '(' Value ',' Value ',' Value ')'
-    return ParseOperation(CurRec);
+    return ParseOperation(CurRec, ItemType);
   }
   }
 
diff --git a/lib/TableGen/TGParser.h b/lib/TableGen/TGParser.h
index 6fd442a7c21..9f4b7e90826 100644
--- a/lib/TableGen/TGParser.h
+++ b/lib/TableGen/TGParser.h
@@ -181,7 +181,7 @@ private:  // Parser methods.
   std::vector<unsigned> ParseRangeList();
   bool ParseRangePiece(std::vector<unsigned> &Ranges);
   RecTy *ParseType();
-  Init *ParseOperation(Record *CurRec);
+  Init *ParseOperation(Record *CurRec, RecTy *ItemType);
   RecTy *ParseOperatorType();
   Init *ParseObjectName(MultiClass *CurMultiClass);
   Record *ParseClassID();
diff --git a/test/TableGen/if-empty-list-arg.td b/test/TableGen/if-empty-list-arg.td
new file mode 100644
index 00000000000..39edf58ff29
--- /dev/null
+++ b/test/TableGen/if-empty-list-arg.td
@@ -0,0 +1,7 @@
+// RUN: llvm-tblgen %s
+// XFAIL: vg_leak
+
+class C<bit cond> {
+  list<int> X = !if(cond, [1, 2, 3], []);
+  list<int> Y = !if(cond, [], [4, 5, 6]);
+}